Introduce intent for TFW messages and fix FSM related bugs

tfw/internals/crypto/authentication.py

@@ -12,6 +12,7 @@ from tfw.internals.networking import message_bytes
 
 def sign_message(key, message):
     message.pop('scope', None)
+    message.pop('intent', None)
     message.pop('signature', None)
     signature = message_signature(key, message)
     message['signature'] = b64encode(signature).decode()
@@ -23,6 +24,7 @@ def message_signature(key, message):
 
 def verify_message(key, message):
     message.pop('scope', None)
+    message.pop('intent', None)
     message = deepcopy(message)
     try:
         signature_b64 = message.pop('signature')

tfw/internals/event_handling/__init__.py

@@ -1,4 +1,5 @@
 from .event_handler import EventHandler
 from .event_handler_factory_base import EventHandlerFactoryBase
+from .control_event_handler import ControlEventHandler
 from .fsm_aware_event_handler import FSMAwareEventHandler
 from .signed_event_handler import SignedEventHandler

tfw/internals/event_handling/control_event_handler.py

@@ -0,0 +1,9 @@
+from tfw.internals.networking import Intent
+
+from .event_handler import EventHandler
+
+
+class ControlEventHandler(EventHandler): # pylint: disable=abstract-method
+    def _event_callback(self, message):
+        if message.get('intent') != Intent.EVENT.value:
+            self.handle_event(message, self.connector)

tfw/internals/event_handling/fsm_aware.py

@@ -7,6 +7,7 @@ LOG = logging.getLogger(__name__)
 
 class FSMAware:
     keys = ['fsm.update']
+
     def __init__(self):
         self.fsm_state = None
         self.fsm_in_accepted_state = False

tfw/internals/event_handling/signed_event_handler.py

@@ -2,13 +2,13 @@ import logging
 
 from tfw.internals.crypto import KeyManager, verify_message
 
-from .event_handler import EventHandler
+from .control_event_handler import ControlEventHandler
 
 LOG = logging.getLogger(__name__)
 
 
 # pylint: disable=abstract-method
-class SignedEventHandler(EventHandler):
+class SignedEventHandler(ControlEventHandler):
     def __init__(self, connector):
         self._auth_key = KeyManager().auth_key
         super().__init__(connector)

tfw/internals/networking/__init__.py

@@ -2,3 +2,4 @@ from .serialization import serialize_tfw_msg, deserialize_tfw_msg, with_deserial
 from .zmq_connector import ZMQConnector, ZMQDownlinkConnector, ZMQUplinkConnector
 from .zmq_listener import ZMQListener
 from .scope import Scope
+from .intent import Intent

tfw/internals/networking/intent.py

@@ -0,0 +1,6 @@
+from enum import Enum
+
+
+class Intent(Enum):
+    CONTROL = 'control'
+    EVENT = 'event'

tfw/internals/networking/zmq_connector.py

@@ -4,6 +4,7 @@ import zmq
 from zmq.eventloop.zmqstream import ZMQStream
 
 from .scope import Scope
+from .intent import Intent
 from .serialization import (
     serialize_tfw_msg,
     deserialize_tfw_msg,
@@ -51,8 +52,10 @@ class ZMQUplinkConnector:
         self._zmq_push_socket.setsockopt(zmq.SNDHWM, 0)
         self._zmq_push_socket.connect(connect_addr)
 
-    def send_message(self, message, scope=Scope.ZMQ):
+    def send_message(self, message, scope=Scope.ZMQ, intent=None):
         message['scope'] = scope.value
+        if isinstance(intent, Intent):
+            message['intent'] = intent.value
         self._zmq_push_socket.send_multipart(serialize_tfw_msg(message))
 
     def close(self):